The electric mandolin is an instrument tuned and played as the mandolin and amplified in similar fashion to an electric guitar. As with electric guitars, electric mandolins take many forms:
Electric mandolins were built in the United States as early as the late 1920s. Among the first companies to produce them were Stromberg-Voisinet, Electro (which later became Rickenbacker), Vivi-Tone, and National Reso-Phonic. Gibson and Vega introduced their electric mandolins in 1936.
In the United States, luthier/inventor Paul Bigsby began building solidbody electric mandolins (technically, they consisted of a solid wood core housing the electronics, with hollow wings forming the body) in 1949. His first one had 10 strings and was built for Al Giddings. Other Bigsby electric mandolin players were multi-instrumentalist Paul Buskirk, Johnny Muessig, and Eschol Cosby. Bigsby's most famous mandolin, built in 1952, was owned and played by Western swing musician Tiny Moore. This instrument had 5 single courses rather than the more common four double courses, and was patterned after a similar instrument built by Jim Harvey of La Jolla, California, for a player named Scotty Broyles. Gibson and Rickenbacker introduced solidbody 8-string mandolins in the 1950s, while Fender followed the single-course idea with its 4-string version.
A related instrument, the Bahian guitar, was developed in Brazil beginning in the 1940s. Bahian guitars typically have a solid body and 4 or 5 single-course strings tuned in fifths, but are considered to be electric versions of the cavaquinho rather than the mandolin.
Both four string single course and eight string double course solid body mandolins have been produced by several makers, as well as five string single course models.
From 1956 to 1976, Fender produced a four string version which they simply called the Fender Electric Mandolin. Its body shape was based on a smaller version of the body. They currently produce an eight string semi-acoustic electric mandolin with a very similar body shape. They also currently produce a revived version of the Fender Electric Mandolin concept, called Mando-Strat; both the 4-string replica and an 8-string version are available.